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<title>FatFs - f_getfree</title>
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<div class="para">
<h2>f_getfree</h2>
<p>The f_getfree function gets number of the free clusters.</p>
<pre>
FRESULT f_getfree (
const char* <em>Path</em>, /* Root directory of the drive */
DWORD* <em>Clusters</em>, /* Pointer to the variable to store number of free clusters */
FATFS** <em>FileSystemObject</em> /* Pointer to pointer to file system object */
);
</pre>
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<div class="para">
<h4>Parameters</h4>
<dl class="par">
<dt>Path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">root directory</a> of the logical drive. Always specify a null-string for Tiny-FatFs.</dd>
<dt>Clusters</dt>
<dd>Pointer to the DWORD variable to store number of free clusters.</dd>
<dt>FileSystemObject</dt>
<dd>Pointer to the pointer that to be stored the pointer to corresponding file system object.</dd>
</dl>
</div>
<div class="para">
<h4>Return Values</h4>
<dl class="ret">
<dt>FR_OK (0)</dt>
<dd>The function succeeded. The <tt><em>*Clusters</em></tt> havs number of free clusters and <tt><em>*FileSystemObject</em></tt> points the file system object.</dd>
<dt>FR_INVALID_DRIVE</dt>
<dd>The drive number is invalid.</dd>
<dt>FR_NOT_READY</dt>
<dd>The disk drive cannot work due to no medium in the drive or any other reason.</dd>
<dt>FR_RW_ERROR</dt>
<dd>Any error occured in low level disk I/O.</dd>
<dt>FR_NOT_ENABLED</dt>
<dd>The logical drive has no work area.</dd>
<dt>FR_NO_FILESYSTEM</dt>
<dd>There is no valid FAT partition on the disk.</dd>
</dl>
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<div class="para">
<h4>Descriptions</h4>
<p>The f_getfree function gets number of free clusters on the drive. The <tt>sects_clust</tt> member in the file system object refreting number of sectors per cluster, so that the free space in unit of sector can be calcurated with this. This function is not supported in read-only configuration and minimization level of >= 1.</p>
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<div class="para">
<h4>Samples Code</h4>
<pre>
FATFS *fs;
DWORD clust;
// Get free clusters
res = f_getfree("", &clust, &fs);
if (res) die(res);
// Get free space
printf("%lu KB total disk space.\n"
"%lu KB available on the disk.\n",
(fs->max_clust - 2) * fs->sects_clust / 2,
clust * fs->sects_clust / 2);
</pre>
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<div class="para">
<h4>References</h4>
<p><tt><a href="sfatfs.html">FATFS</a></tt></p>
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<p class="foot"><a href="../00index_e.html">Return</a></p>
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